The present invention relates generally to equipment for the handling of electronic components and, more particularly, to a detaping apparatus for the removal of surface mount components from carrier tapes.
In the process for handling surface mount components known as "tape and reel" the surface mount components are inserted into pockets which are formed in a carrier tape and then a cover tape is applied over the components and heat sealed to the carrier tape thereby covering the components. The process of detaping involves the removal of the components from the carrier tape for reuse.
In the conventional manual detaping process, the carrier tape is cut into strips, each approximately six inches in length, using scissors. The cover tape is then peeled off by hand. The carrier tape is inverted allowing the surface mount components to fall onto a work surface. The operator then manually picks up the components one at a time and inserts them into a plastic tube.
Using the above manual process, an operator can pick up and insert approximately 1,000 surface mount components per hour. However, the manual handling of the surface mount components can cause physical damage to the components such as bending of the leads, which are relatively small and easily damaged, and the manual process can also cause functional damage resulting from electrostatic charges. In addition, corrosion and oxidation may begin to form on the components due to acid in sweat coming into contact with the components during the handling process.
The prior art also includes various attempts to automate the detaping process including the following U.S. Pat. Nos. 4,494,902 issued to Kuppenset et al.; 4,660,282 issued to Pfaff; 4,735,341 issued to Hamilton et al.; 4,738,386 issued to Itemadani et al.; 4,869,393 issued to Soth; 4,915,770 issued to Haeda et al.; 5,150,787 issued to Bird et al.; 5,268,059 issued to Olson; and 5,213,653 issued to Akahori et al.
Of the above U.S. Patents only U.S. Pat. No. 5,269,059 issued to Olson and U.S. Pat. No. 4,869,393 to Soth are generally similar in purpose to the detaping apparatus of the present invention. However, examination of these patents indicates significant limitations and differences between these devices and the apparatus according to the present invention.
U.S. Pat. No. 4,869,393 to Soth shows a device which is highly complex in construction and in which the actions of feeding and peeling are performed separately. The device includes a guide surface which is moved in a peeling direction. This results in a device which is composed of a relatively large number of complex mechanical components.
U.S. Pat. No. 5,268,059 to Olson shows a device in which the peeling of the cover tape provides a forward motion to the carrier tape and in which a square opening is provided through which the components fall in a direction which is generally parallel to the direction of motion of the tape carrier. This device is suitable for detaping plastic leaded chip carriers, however it cannot be used for small outline package components.
Plastic leaded chip carriers have leads on all four sides of a chip and therefore these components are designed so as to permit the leads to touch each other in a plastic storage tube without damage. The in-line operation of the Olson device therefore has no adverse effect on the plastic leaded chip carrier components however, small outline components have leads only on the opposite edges of a chip. When these components are in a carrier tape the walls of the pockets of the carrier tape serve to protect the leads from touching each other. Small outline packages are designed so that the blank edges touch each other when the components are in a plastic tube and the blank edges of the components are parallel to the longitudinal edges of the carrier tape. The Olson device releases the components in a direction which is in line with the direction of motion of the carrier tape. If a carrier tape containing small outline packages were inserted in the Olson device, the components would be released into the plastic tube in a direction which would allow the leads on adjacent components to become entangled and thereby become damaged.